Correlation between CD14+CD16++ monocytes in peripheral blood and hypertriglyceridemia after allograft renal transplantation

Changes in phenotypic patterns of blood monocytes after kidney transplantation and during acute rejection

Peripheral blood monocytes, which serve as precursors for tissue macrophages and dendritic cells (DC), play a key role in the immune response to kidney allograft, reparation processes and homeostasis regulation. In this prospective study, we used multicolor flow cytometry to monitor the phenotypic patterns of peripheral monocytes in subjects with uncomplicated outcomes and those with acute rejection. We found a reciprocal increase in the proportion of "classical monocytes" (CD14+CD16-) along with a decline in pro-inflammatory "intermediary" (CD14+CD16+) and "non-classical" (CD14lowCD16+) monocytes in subjects with normal outcomes. In subjects with acute rejection, we observed no reduction in "intermediary" monocytes and no increase in "classical" monocytes. Patients with uncomplicated outcomes exhibited downregulated HLA-DR in all three monocyte subpopulations. However, non-classical monocytes were unaffected in subjects with acute rejection. Expression of CD47 was downregulated after transplantation, while patients with antibody-mediated rejection and donor-specific antibodies showed higher pre-transplant values. In monocytes isolated at the time of biopsy, CD47 expression was higher in individuals with acute rejection compared to patients with normal outcomes one year post-transplant. Expression of CD209 (DC-SIGN) and the proportion of CD163+CD206+ subpopulations were upregulated during the first week after kidney transplantation. CD209 was also upregulated in samples taken on the day of biopsy confirming acute rejection. Our data demonstrate that kidney allograft transplantation is associated with phenotypic changes in peripheral blood monocytes during acute rejection.

Intermediate CD14++CD16+ monocyte predicts severe coronary stenosis and extensive plaque involvement in asymptomatic individuals

Circulating leukocyte subtypes and monocyte subsets are independent predictors of cardiovascular events. We hypothesized that an increased leukocyte subtype would predict severe coronary stenosis and extensive plaque involvement. We retrospectively analyzed clinical, laboratory, and coronary CT data in a total of 588 asymptomatic adults (69% men; mean age, 57 ± 9 years) undergoing a general health check-up. Intermediate CD14⁺⁺CD16⁺ monocyte count had the strongest association with mixed and calcified plaque scores, whereas the numbers of neutrophils and classical CD14⁺⁺CD16^- monocytes were significantly associated with non-calcified plaque score. Only high CD14⁺⁺CD16⁺ monocyte count (>12 cells/μL) significantly predicted extensive plaque involvement [odds ratio 3.16 (95% confidence interval 1.84-5.43), P < 0.001; quartile 4 vs. 1-3] and severe coronary stenosis [3.67 (1.84-7.33), P < 0.001; quartile 4 vs. 1-3] after adjustments for Framingham Risk Score (FRS), metabolic syndrome, and C-reactive protein. The CD14⁺⁺CD16⁺ monocyte count, when added to FRS, significantly reclassified 30.4 and 26.7% of the overall and 50.2 and 36.2% of the intermediate-risk population (FRS 6-20%) for predicting extensive plaque involvement and severe coronary stenosis, respectively. Thus, in asymptomatic individuals, intermediate CD14⁺⁺CD16⁺ monocyte could independently predict severe CAD and improve risk stratification.